Wednesday, January 27, 2010

The law of unintended consequences as applied to the hole in the ozone

Some people remember exactly where they were the day the first men walked on the moon; I happen to remember exactly where I was when I first heard there was a hole in the ozone layer: summer, 1985, sitting at a picnic table at Nickerson State Park in Brewster, with my radio tuned to All Things Considered.. A hole in the ozone? Inconceivable!

How quickly we can become accustomed to truly bad news, especially if the consequences are not immediately apparent-- although the nearly 1,000,000 U.S. residents who discovered they had skin cancer in 1985 would certainly disagree with me. 1985 was also the year that President Ronald Reagan declared the first National Skin Cancer Detection and Prevention Week, although he'd spent the first three years of his administration fighting regulation of chlorofluorocarbons, the chief but not sole cause of ozone thinning and, at the time, ubiquitous in aerosol sprays and air conditioning units.

So who's kept track of the hole in the ozone layer, which at times can be nearly twice the size of the continental U.S.? (This is not a tidy little hole, by the way, with clear margins, but instead manifests as gradations in thinning.) Many of us remember the slow phase-out of chlorofluorocarbons; we hoped the ozone layer could begin to repair itself.

That repair is slowly happening, although at the current rate, we won't reach pre-1980 levels until at least 2060. But it turns out this good news has its dark side: in the Antarctic, high winds caused by the hole created moist, bright, fluffy clouds which also shielded the Antarctic from some of the effects of global warming, according to researchers published in today's Geophysical Research Letters, The New York Times covered this report on January 25, as well as that of a dissenting voice, who feels that the effects of global warming itself will keep the high winds blowing, protecting the Antarctic. Is this a good thing or a bad thing? Gee, can't we have it all? A repaired ozone hole and a reduction of global warming?Graphics from The Ozone Hole